A 33-year-old man comes to the clinic for liver function tests before starting a selective serotonin reuptake inhibitor

A 33-year-old man comes to the clinic for liver function tests before starting a selective serotonin reuptake inhibitor (SSRI) treatment. Lab studies show an AST concentration of 62 U/L and an ALT concentration of 31 U/L. Bilirubin and alkaline phosphatase are normal. CBC, BUN, creatinine, and CPK concentrations are normal. Amylase concentration is slightly elevated. CT scan shows epigastric calcifications and hepatomegaly. Physical examination shows hepatomegaly and ascites with a positive fluid wave. No obstructions are seen. Liver biopsy shows micronodular fibrosis. Hepatitis serologies are all negative. Which of the following is the most likely cause of the patient’s liver function test abnormalities?